I am going to pick up a MF-12 Hydro that I am buying from a local Massey dealer tomorrow the price is $75 its a starter/generator setup. All original aluminum dash and nose, good shape all together. I know a lot about the MF-10 gearshift setups but have no knowledge of the hydro transmissions and I am curious on what to look for in terms of problems if it has any? Either way I am buying this tractor which I can either run or use for parts. But If I do decide to eventually use this tractor and not for parts I want to know the ins and outs of the hydro transmission. Any comments would be great.

The biggest problem is that 12 hydro will make your other tractors green with envy at the big tractor styling it has! Of course if they are green already, you won't notice the difference!

On a more serious note, what I've noticed on my two hydros is that the control mechanisms wear a bit, depending on how the machine is maintained. The cam follower is a sleeve bearing and can get a groove worn in it. I replaced mine with a 1/2 x 1/4 bearing from WW Grainger. Also, the control shaft on both mine has leaked and needed a replacement "O" ring, which I again sourced from Grainger. If yours is early enough that it has the aluminum nose piece, it probably doesn't have an overflow tank. I have an early one with no tank, and after operating it for a year decided to add one. While it operated ok without one, it wasn't easy to keep full as it tended to heat up, expand the oil in the reservoir and then overflow. I added a tank last fall and have been happy thus far. Here is a post on how and where I put an overflow tank.

Another thing to look for is a cracked frame.you'll have to remove the foot rests to check it out.They usually are cracked right were the front of the seat mount is.Also another thing that has me curious is the alum dash and nose pc.That was only avail on the 66 10.The first year that the 12 was avail was I believe 67 only in hydro.They didn't come w/alum it was only fiber glass dash and nose pc.It must've been changed sometime.Still is a good buy though.The dash and nose pc are worth that.Does it run?

Another thing to look for is a cracked frame.you'll have to remove the foot rests to check it out.They usually are cracked right were the front of the seat mount is.Also another thing that has me curious is the alum dash and nose pc.That was only avail on the 66 10.The first year that the 12 was avail was I believe 67 only in hydro.They didn't come w/alum it was only fiber glass dash and nose pc.It must've been changed sometime.Still is a good buy though.The dash and nose pc are worth that.Does it run?

Oh, cracked frame? I thought he asked about the transmission itself. See my posts here about my cracked frame discovery and repair.